1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2021, MediaTek Inc.
4  * Copyright (c) 2021-2022, Intel Corporation.
5  *
6  * Authors:
7  *  Amir Hanania <amir.hanania@intel.com>
8  *  Haijun Liu <haijun.liu@mediatek.com>
9  *  Moises Veleta <moises.veleta@intel.com>
10  *  Ricardo Martinez <ricardo.martinez@linux.intel.com>
11  *
12  * Contributors:
13  *  Andy Shevchenko <andriy.shevchenko@linux.intel.com>
14  *  Chandrashekar Devegowda <chandrashekar.devegowda@intel.com>
15  *  Chiranjeevi Rapolu <chiranjeevi.rapolu@intel.com>
16  *  Eliot Lee <eliot.lee@intel.com>
17  *  Sreehari Kancharla <sreehari.kancharla@intel.com>
18  */
19 
20 #include <linux/bits.h>
21 #include <linux/bitfield.h>
22 #include <linux/device.h>
23 #include <linux/gfp.h>
24 #include <linux/kernel.h>
25 #include <linux/kthread.h>
26 #include <linux/list.h>
27 #include <linux/mutex.h>
28 #include <linux/netdevice.h>
29 #include <linux/skbuff.h>
30 #include <linux/spinlock.h>
31 #include <linux/wait.h>
32 #include <linux/wwan.h>
33 
34 #include "t7xx_hif_cldma.h"
35 #include "t7xx_modem_ops.h"
36 #include "t7xx_port.h"
37 #include "t7xx_port_proxy.h"
38 #include "t7xx_state_monitor.h"
39 
40 #define Q_IDX_CTRL			0
41 #define Q_IDX_MBIM			2
42 #define Q_IDX_AT_CMD			5
43 
44 #define INVALID_SEQ_NUM			GENMASK(15, 0)
45 
46 #define for_each_proxy_port(i, p, proxy)	\
47 	for (i = 0, (p) = &(proxy)->ports[i];	\
48 	     i < (proxy)->port_count;		\
49 	     i++, (p) = &(proxy)->ports[i])
50 
51 static const struct t7xx_port_conf t7xx_md_port_conf[] = {
52 	{
53 		.tx_ch = PORT_CH_UART2_TX,
54 		.rx_ch = PORT_CH_UART2_RX,
55 		.txq_index = Q_IDX_AT_CMD,
56 		.rxq_index = Q_IDX_AT_CMD,
57 		.txq_exp_index = 0xff,
58 		.rxq_exp_index = 0xff,
59 		.path_id = CLDMA_ID_MD,
60 		.ops = &wwan_sub_port_ops,
61 		.name = "AT",
62 		.port_type = WWAN_PORT_AT,
63 	}, {
64 		.tx_ch = PORT_CH_MBIM_TX,
65 		.rx_ch = PORT_CH_MBIM_RX,
66 		.txq_index = Q_IDX_MBIM,
67 		.rxq_index = Q_IDX_MBIM,
68 		.path_id = CLDMA_ID_MD,
69 		.ops = &wwan_sub_port_ops,
70 		.name = "MBIM",
71 		.port_type = WWAN_PORT_MBIM,
72 	}, {
73 #ifdef CONFIG_WWAN_DEBUGFS
74 		.tx_ch = PORT_CH_MD_LOG_TX,
75 		.rx_ch = PORT_CH_MD_LOG_RX,
76 		.txq_index = 7,
77 		.rxq_index = 7,
78 		.txq_exp_index = 7,
79 		.rxq_exp_index = 7,
80 		.path_id = CLDMA_ID_MD,
81 		.ops = &t7xx_trace_port_ops,
82 		.name = "mdlog",
83 	}, {
84 #endif
85 		.tx_ch = PORT_CH_CONTROL_TX,
86 		.rx_ch = PORT_CH_CONTROL_RX,
87 		.txq_index = Q_IDX_CTRL,
88 		.rxq_index = Q_IDX_CTRL,
89 		.path_id = CLDMA_ID_MD,
90 		.ops = &ctl_port_ops,
91 		.name = "t7xx_ctrl",
92 	},
93 };
94 
95 static struct t7xx_port *t7xx_proxy_get_port_by_ch(struct port_proxy *port_prox, enum port_ch ch)
96 {
97 	const struct t7xx_port_conf *port_conf;
98 	struct t7xx_port *port;
99 	int i;
100 
101 	for_each_proxy_port(i, port, port_prox) {
102 		port_conf = port->port_conf;
103 		if (port_conf->rx_ch == ch || port_conf->tx_ch == ch)
104 			return port;
105 	}
106 
107 	return NULL;
108 }
109 
110 static u16 t7xx_port_next_rx_seq_num(struct t7xx_port *port, struct ccci_header *ccci_h)
111 {
112 	u32 status = le32_to_cpu(ccci_h->status);
113 	u16 seq_num, next_seq_num;
114 	bool assert_bit;
115 
116 	seq_num = FIELD_GET(CCCI_H_SEQ_FLD, status);
117 	next_seq_num = (seq_num + 1) & FIELD_MAX(CCCI_H_SEQ_FLD);
118 	assert_bit = status & CCCI_H_AST_BIT;
119 	if (!assert_bit || port->seq_nums[MTK_RX] == INVALID_SEQ_NUM)
120 		return next_seq_num;
121 
122 	if (seq_num != port->seq_nums[MTK_RX])
123 		dev_warn_ratelimited(port->dev,
124 				     "seq num out-of-order %u != %u (header %X, len %X)\n",
125 				     seq_num, port->seq_nums[MTK_RX],
126 				     le32_to_cpu(ccci_h->packet_header),
127 				     le32_to_cpu(ccci_h->packet_len));
128 
129 	return next_seq_num;
130 }
131 
132 void t7xx_port_proxy_reset(struct port_proxy *port_prox)
133 {
134 	struct t7xx_port *port;
135 	int i;
136 
137 	for_each_proxy_port(i, port, port_prox) {
138 		port->seq_nums[MTK_RX] = INVALID_SEQ_NUM;
139 		port->seq_nums[MTK_TX] = 0;
140 	}
141 }
142 
143 static int t7xx_port_get_queue_no(struct t7xx_port *port)
144 {
145 	const struct t7xx_port_conf *port_conf = port->port_conf;
146 	struct t7xx_fsm_ctl *ctl = port->t7xx_dev->md->fsm_ctl;
147 
148 	return t7xx_fsm_get_md_state(ctl) == MD_STATE_EXCEPTION ?
149 		port_conf->txq_exp_index : port_conf->txq_index;
150 }
151 
152 static void t7xx_port_struct_init(struct t7xx_port *port)
153 {
154 	INIT_LIST_HEAD(&port->entry);
155 	INIT_LIST_HEAD(&port->queue_entry);
156 	skb_queue_head_init(&port->rx_skb_list);
157 	init_waitqueue_head(&port->rx_wq);
158 	port->seq_nums[MTK_RX] = INVALID_SEQ_NUM;
159 	port->seq_nums[MTK_TX] = 0;
160 	atomic_set(&port->usage_cnt, 0);
161 }
162 
163 struct sk_buff *t7xx_port_alloc_skb(int payload)
164 {
165 	struct sk_buff *skb = __dev_alloc_skb(payload + sizeof(struct ccci_header), GFP_KERNEL);
166 
167 	if (skb)
168 		skb_reserve(skb, sizeof(struct ccci_header));
169 
170 	return skb;
171 }
172 
173 struct sk_buff *t7xx_ctrl_alloc_skb(int payload)
174 {
175 	struct sk_buff *skb = t7xx_port_alloc_skb(payload + sizeof(struct ctrl_msg_header));
176 
177 	if (skb)
178 		skb_reserve(skb, sizeof(struct ctrl_msg_header));
179 
180 	return skb;
181 }
182 
183 /**
184  * t7xx_port_enqueue_skb() - Enqueue the received skb into the port's rx_skb_list.
185  * @port: port context.
186  * @skb: received skb.
187  *
188  * Return:
189  * * 0		- Success.
190  * * -ENOBUFS	- Not enough buffer space. Caller will try again later, skb is not consumed.
191  */
192 int t7xx_port_enqueue_skb(struct t7xx_port *port, struct sk_buff *skb)
193 {
194 	unsigned long flags;
195 
196 	spin_lock_irqsave(&port->rx_wq.lock, flags);
197 	if (port->rx_skb_list.qlen >= port->rx_length_th) {
198 		spin_unlock_irqrestore(&port->rx_wq.lock, flags);
199 
200 		return -ENOBUFS;
201 	}
202 	__skb_queue_tail(&port->rx_skb_list, skb);
203 	spin_unlock_irqrestore(&port->rx_wq.lock, flags);
204 
205 	wake_up_all(&port->rx_wq);
206 	return 0;
207 }
208 
209 static int t7xx_port_send_raw_skb(struct t7xx_port *port, struct sk_buff *skb)
210 {
211 	enum cldma_id path_id = port->port_conf->path_id;
212 	struct cldma_ctrl *md_ctrl;
213 	int ret, tx_qno;
214 
215 	md_ctrl = port->t7xx_dev->md->md_ctrl[path_id];
216 	tx_qno = t7xx_port_get_queue_no(port);
217 	ret = t7xx_cldma_send_skb(md_ctrl, tx_qno, skb);
218 	if (ret)
219 		dev_err(port->dev, "Failed to send skb: %d\n", ret);
220 
221 	return ret;
222 }
223 
224 static int t7xx_port_send_ccci_skb(struct t7xx_port *port, struct sk_buff *skb,
225 				   unsigned int pkt_header, unsigned int ex_msg)
226 {
227 	const struct t7xx_port_conf *port_conf = port->port_conf;
228 	struct ccci_header *ccci_h;
229 	u32 status;
230 	int ret;
231 
232 	ccci_h = skb_push(skb, sizeof(*ccci_h));
233 	status = FIELD_PREP(CCCI_H_CHN_FLD, port_conf->tx_ch) |
234 		 FIELD_PREP(CCCI_H_SEQ_FLD, port->seq_nums[MTK_TX]) | CCCI_H_AST_BIT;
235 	ccci_h->status = cpu_to_le32(status);
236 	ccci_h->packet_header = cpu_to_le32(pkt_header);
237 	ccci_h->packet_len = cpu_to_le32(skb->len);
238 	ccci_h->ex_msg = cpu_to_le32(ex_msg);
239 
240 	ret = t7xx_port_send_raw_skb(port, skb);
241 	if (ret)
242 		return ret;
243 
244 	port->seq_nums[MTK_TX]++;
245 	return 0;
246 }
247 
248 int t7xx_port_send_ctl_skb(struct t7xx_port *port, struct sk_buff *skb, unsigned int msg,
249 			   unsigned int ex_msg)
250 {
251 	struct ctrl_msg_header *ctrl_msg_h;
252 	unsigned int msg_len = skb->len;
253 	u32 pkt_header = 0;
254 
255 	ctrl_msg_h = skb_push(skb, sizeof(*ctrl_msg_h));
256 	ctrl_msg_h->ctrl_msg_id = cpu_to_le32(msg);
257 	ctrl_msg_h->ex_msg = cpu_to_le32(ex_msg);
258 	ctrl_msg_h->data_length = cpu_to_le32(msg_len);
259 
260 	if (!msg_len)
261 		pkt_header = CCCI_HEADER_NO_DATA;
262 
263 	return t7xx_port_send_ccci_skb(port, skb, pkt_header, ex_msg);
264 }
265 
266 int t7xx_port_send_skb(struct t7xx_port *port, struct sk_buff *skb, unsigned int pkt_header,
267 		       unsigned int ex_msg)
268 {
269 	struct t7xx_fsm_ctl *ctl = port->t7xx_dev->md->fsm_ctl;
270 	unsigned int fsm_state;
271 
272 	fsm_state = t7xx_fsm_get_ctl_state(ctl);
273 	if (fsm_state != FSM_STATE_PRE_START) {
274 		const struct t7xx_port_conf *port_conf = port->port_conf;
275 		enum md_state md_state = t7xx_fsm_get_md_state(ctl);
276 
277 		switch (md_state) {
278 		case MD_STATE_EXCEPTION:
279 			if (port_conf->tx_ch != PORT_CH_MD_LOG_TX)
280 				return -EBUSY;
281 			break;
282 
283 		case MD_STATE_WAITING_FOR_HS1:
284 		case MD_STATE_WAITING_FOR_HS2:
285 		case MD_STATE_STOPPED:
286 		case MD_STATE_WAITING_TO_STOP:
287 		case MD_STATE_INVALID:
288 			return -ENODEV;
289 
290 		default:
291 			break;
292 		}
293 	}
294 
295 	return t7xx_port_send_ccci_skb(port, skb, pkt_header, ex_msg);
296 }
297 
298 static void t7xx_proxy_setup_ch_mapping(struct port_proxy *port_prox)
299 {
300 	struct t7xx_port *port;
301 
302 	int i, j;
303 
304 	for (i = 0; i < ARRAY_SIZE(port_prox->rx_ch_ports); i++)
305 		INIT_LIST_HEAD(&port_prox->rx_ch_ports[i]);
306 
307 	for (j = 0; j < ARRAY_SIZE(port_prox->queue_ports); j++) {
308 		for (i = 0; i < ARRAY_SIZE(port_prox->queue_ports[j]); i++)
309 			INIT_LIST_HEAD(&port_prox->queue_ports[j][i]);
310 	}
311 
312 	for_each_proxy_port(i, port, port_prox) {
313 		const struct t7xx_port_conf *port_conf = port->port_conf;
314 		enum cldma_id path_id = port_conf->path_id;
315 		u8 ch_id;
316 
317 		ch_id = FIELD_GET(PORT_CH_ID_MASK, port_conf->rx_ch);
318 		list_add_tail(&port->entry, &port_prox->rx_ch_ports[ch_id]);
319 		list_add_tail(&port->queue_entry,
320 			      &port_prox->queue_ports[path_id][port_conf->rxq_index]);
321 	}
322 }
323 
324 static struct t7xx_port *t7xx_port_proxy_find_port(struct t7xx_pci_dev *t7xx_dev,
325 						   struct cldma_queue *queue, u16 channel)
326 {
327 	struct port_proxy *port_prox = t7xx_dev->md->port_prox;
328 	struct list_head *port_list;
329 	struct t7xx_port *port;
330 	u8 ch_id;
331 
332 	ch_id = FIELD_GET(PORT_CH_ID_MASK, channel);
333 	port_list = &port_prox->rx_ch_ports[ch_id];
334 	list_for_each_entry(port, port_list, entry) {
335 		const struct t7xx_port_conf *port_conf = port->port_conf;
336 
337 		if (queue->md_ctrl->hif_id == port_conf->path_id &&
338 		    channel == port_conf->rx_ch)
339 			return port;
340 	}
341 
342 	return NULL;
343 }
344 
345 /**
346  * t7xx_port_proxy_recv_skb() - Dispatch received skb.
347  * @queue: CLDMA queue.
348  * @skb: Socket buffer.
349  *
350  * Return:
351  ** 0		- Packet consumed.
352  ** -ERROR	- Failed to process skb.
353  */
354 static int t7xx_port_proxy_recv_skb(struct cldma_queue *queue, struct sk_buff *skb)
355 {
356 	struct ccci_header *ccci_h = (struct ccci_header *)skb->data;
357 	struct t7xx_pci_dev *t7xx_dev = queue->md_ctrl->t7xx_dev;
358 	struct t7xx_fsm_ctl *ctl = t7xx_dev->md->fsm_ctl;
359 	struct device *dev = queue->md_ctrl->dev;
360 	const struct t7xx_port_conf *port_conf;
361 	struct t7xx_port *port;
362 	u16 seq_num, channel;
363 	int ret;
364 
365 	channel = FIELD_GET(CCCI_H_CHN_FLD, le32_to_cpu(ccci_h->status));
366 	if (t7xx_fsm_get_md_state(ctl) == MD_STATE_INVALID) {
367 		dev_err_ratelimited(dev, "Packet drop on channel 0x%x, modem not ready\n", channel);
368 		goto drop_skb;
369 	}
370 
371 	port = t7xx_port_proxy_find_port(t7xx_dev, queue, channel);
372 	if (!port) {
373 		dev_err_ratelimited(dev, "Packet drop on channel 0x%x, port not found\n", channel);
374 		goto drop_skb;
375 	}
376 
377 	seq_num = t7xx_port_next_rx_seq_num(port, ccci_h);
378 	port_conf = port->port_conf;
379 	skb_pull(skb, sizeof(*ccci_h));
380 
381 	ret = port_conf->ops->recv_skb(port, skb);
382 	/* Error indicates to try again later */
383 	if (ret) {
384 		skb_push(skb, sizeof(*ccci_h));
385 		return ret;
386 	}
387 
388 	port->seq_nums[MTK_RX] = seq_num;
389 	return 0;
390 
391 drop_skb:
392 	dev_kfree_skb_any(skb);
393 	return 0;
394 }
395 
396 /**
397  * t7xx_port_proxy_md_status_notify() - Notify all ports of state.
398  *@port_prox: The port_proxy pointer.
399  *@state: State.
400  *
401  * Called by t7xx_fsm. Used to dispatch modem status for all ports,
402  * which want to know MD state transition.
403  */
404 void t7xx_port_proxy_md_status_notify(struct port_proxy *port_prox, unsigned int state)
405 {
406 	struct t7xx_port *port;
407 	int i;
408 
409 	for_each_proxy_port(i, port, port_prox) {
410 		const struct t7xx_port_conf *port_conf = port->port_conf;
411 
412 		if (port_conf->ops->md_state_notify)
413 			port_conf->ops->md_state_notify(port, state);
414 	}
415 }
416 
417 static void t7xx_proxy_init_all_ports(struct t7xx_modem *md)
418 {
419 	struct port_proxy *port_prox = md->port_prox;
420 	struct t7xx_port *port;
421 	int i;
422 
423 	for_each_proxy_port(i, port, port_prox) {
424 		const struct t7xx_port_conf *port_conf = port->port_conf;
425 
426 		t7xx_port_struct_init(port);
427 
428 		if (port_conf->tx_ch == PORT_CH_CONTROL_TX)
429 			md->core_md.ctl_port = port;
430 
431 		port->t7xx_dev = md->t7xx_dev;
432 		port->dev = &md->t7xx_dev->pdev->dev;
433 		spin_lock_init(&port->port_update_lock);
434 		port->chan_enable = false;
435 
436 		if (port_conf->ops->init)
437 			port_conf->ops->init(port);
438 	}
439 
440 	t7xx_proxy_setup_ch_mapping(port_prox);
441 }
442 
443 static int t7xx_proxy_alloc(struct t7xx_modem *md)
444 {
445 	unsigned int port_count = ARRAY_SIZE(t7xx_md_port_conf);
446 	struct device *dev = &md->t7xx_dev->pdev->dev;
447 	struct port_proxy *port_prox;
448 	int i;
449 
450 	port_prox = devm_kzalloc(dev, sizeof(*port_prox) + sizeof(struct t7xx_port) * port_count,
451 				 GFP_KERNEL);
452 	if (!port_prox)
453 		return -ENOMEM;
454 
455 	md->port_prox = port_prox;
456 	port_prox->dev = dev;
457 
458 	for (i = 0; i < port_count; i++)
459 		port_prox->ports[i].port_conf = &t7xx_md_port_conf[i];
460 
461 	port_prox->port_count = port_count;
462 	t7xx_proxy_init_all_ports(md);
463 	return 0;
464 }
465 
466 /**
467  * t7xx_port_proxy_init() - Initialize ports.
468  * @md: Modem.
469  *
470  * Create all port instances.
471  *
472  * Return:
473  * * 0		- Success.
474  * * -ERROR	- Error code from failure sub-initializations.
475  */
476 int t7xx_port_proxy_init(struct t7xx_modem *md)
477 {
478 	int ret;
479 
480 	ret = t7xx_proxy_alloc(md);
481 	if (ret)
482 		return ret;
483 
484 	t7xx_cldma_set_recv_skb(md->md_ctrl[CLDMA_ID_MD], t7xx_port_proxy_recv_skb);
485 	return 0;
486 }
487 
488 void t7xx_port_proxy_uninit(struct port_proxy *port_prox)
489 {
490 	struct t7xx_port *port;
491 	int i;
492 
493 	for_each_proxy_port(i, port, port_prox) {
494 		const struct t7xx_port_conf *port_conf = port->port_conf;
495 
496 		if (port_conf->ops->uninit)
497 			port_conf->ops->uninit(port);
498 	}
499 }
500 
501 int t7xx_port_proxy_chl_enable_disable(struct port_proxy *port_prox, unsigned int ch_id,
502 				       bool en_flag)
503 {
504 	struct t7xx_port *port = t7xx_proxy_get_port_by_ch(port_prox, ch_id);
505 	const struct t7xx_port_conf *port_conf;
506 
507 	if (!port)
508 		return -EINVAL;
509 
510 	port_conf = port->port_conf;
511 
512 	if (en_flag) {
513 		if (port_conf->ops->enable_chl)
514 			port_conf->ops->enable_chl(port);
515 	} else {
516 		if (port_conf->ops->disable_chl)
517 			port_conf->ops->disable_chl(port);
518 	}
519 
520 	return 0;
521 }
522